#include<stdio.h>
#define M 100

int main()
{
    printf("hello world\n");
    //printf("nihao\n");
    //printf("nihao\n");
    //printf("nihao\n");
    //printf("nihao\n");

#ifdef N
    printf("N\n");
#else
    printf("no N\n");
#endif
	return 0;
}
